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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

8520 results found.

  1. GRB 200228B: KAIT Optical Upper Limit
  2. LIGO/Virgo S200224ca: Updated Sky Localization and EM Bright Classification
  3. IceCube-200227A : Upper limits from Insight-HXMT/HE observations
  4. HAWC-200216A: No Neutrino Counterpart in ANTARES Search
  5. IceCube-200227A: Upper limits from Fermi-GBM Observations
  6. IceCube-200227A: IceCube observation of a high-energy neutrino candidate event
  7. GRB 200227A: Swift detection of a burst
  8. LIGO/Virgo S200225q: Not observable by CALET
  9. LIGO/Virgo S200224ca: Upper limits from CALET observations.
  10. LIGO/Virgo S200225q: Updated Sky Localization
  11. LIGO/Virgo S200224ca: DESGW Optical counterpart candidates from DECam
  12. LIGO/Virgo S200225q: no counterpart candidate in SVOM/GWAC observations
  13. GRB 200219A: Chandra rapid ToO upper limit
  14. LIGO/Virgo S200219ac: Updated Sky Localization
  15. LIGO/Virgo S200225q: Upper limits from Fermi-GBM Observations
  16. LIGO/Virgo S200225q: upper limits from AGILE/GRID observations
  17. LIGO/Virgo S200225q: Upper limits from IceCube neutrino searches
  18. LIGO/Virgo S200225q: No counterpart candidates in HAWC observations
  19. LIGO/Virgo S200225q : no neutrino counterpart candidate in ANTARES search
  20. LIGO/Virgo S200224ca: upper limits from AGILE/GRID observations
  21. LIGO/Virgo S200225q: Identification of a GW compact binary merger candidate The LIGO Scientific Collaboration and the Virgo Collaboration
  22. GRB 200224A: RATIR Optical Observations and Confirmation of the Afterglow
  23. LIGO/Virgo S200224ca: Upper limits from IceCube neutrino searches
  24. LIGO/Virgo S200224ca: Identification of a GW compact binary merger candidate The LIGO Scientific Collaboration and the Virgo Collaboration
  25. GRB 200219C: Swift-XRT afterglow confirmation
  26. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  27. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  28. GRB 200219C: Mondy and TSHAO optical observations
  29. GRB 200219C: DDOTI Observations
  30. GRB 200219C: Tiled Swift observations
  31. LIGO/Virgo S200219ac: Fermi GBM transient event not confidently associated with GW signal
  32. LIGO/Virgo S200219ac: upper limits from AGILE/GRID observations
  33. LIGO/Virgo S200219ac : no neutrino counterpart candidate in ANTARES search
  34. LIGO/Virgo S200219ac: Upper limits from IceCube neutrino searches
  35. LIGO/Virgo S200219ac: No counterpart candidates in HAWC observations
  36. LIGO/Virgo S200219ac: Identification of a GW compact binary merger candidate
  37. GRB 200219A: MASTER catalog automatic possible Host Galaxy candidate
  38. GRB 200219A: Swift detection of a short burst
  39. LIGO/Virgo (S200213t/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  40. GRB 200216B - possible IR counterpart from VLT
  41. GRB 200216B: Swift detection of a burst
  42. LIGO/Virgo S200213t: Updated Sky Localization
  43. LIGO/Virgo S200213t: Updated coverage and candidate list for the Zwicky Transient Facility
  44. LIGO/Virgo S200213t: CLU/NED Galaxies in the 4-Update Localization Volume
  45. LIGO/Virgo S200213t: Updated Sky Localization
  46. LIGO/Virgo S200213t: Lulin Follow-Up Observations
  47. GRB 200215A: Swift detection of a burst
  48. LIGO/Virgo S200213t: MASTER possible Kilonova candidate in PGC315337
  49. LIGO/Virgo S200213t: P200 Spectroscopy of ZTF20aanakcd/AT2020cmr
  50. LIGO/Virgo S200213t: No counterpart candidates from Nanshan-0.6m observations
  51. LIGO/Virgo S200213t: No notable candidates in GOTO imaging
  52. LIGO/Virgo S200213t: One additional candidate from the Zwicky Transient Facility
  53. LIGO/Virgo S200213t: upper limits from AGILE/GRID observations
  54. LIGO/Virgo S200208q: no counterpart candidate in SVOM/C-GFT observations
  55. LIGO/Virgo S200213t : no neutrino counterpart candidate in ANTARES search
  56. LIGO/Virgo S200213t: Neutrino and galaxies cross-match
  57. LIGO/Virgo S200213t: NED Galaxies in the 90% Localization Volume
  58. LIGO/Virgo S200213t: 1 counterpart neutrino candidate from IceCube neutrino searches
  59. LIGO/Virgo S200213t: Identification of a GW compact binary merger candidate
  60. LIGO/Virgo S200208q: Updated Sky Localization
  61. LIGO/Virgo S200208q: Not observable by CALET
  62. LIGO/Virgo S200208q: Upper limits from Fermi-GBM Observations
  63. LIGO/Virgo S200208q : upper limits from AGILE/GRID observations
  64. LIGO/Virgo S200208q: No counterpart candidates in HAWC observations
  65. LIGO/Virgo S200208q : no neutrino counterpart candidate in ANTARES search
  66. LIGO/Virgo S200208q: Upper limits from IceCube neutrino searches
  67. LIGO/Virgo S200208q: Identification of a GW compact binary merger candidate
  68. Swift Trigger 954840 is not a GRB
  69. GRB 200205A = Swift J0840.7-3516, A newly discovered transient X-ray Pulsar
  70. GRB 200205B: Swift detection of a burst with optical counterpart
  71. AMON IceCube-HAWC_200202A : No neutrino counterpart seen with ANTARES
  72. GRB 200131A: Swift detection of a burst with an optical counterpart
  73. LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations
  74. LIGO/Virgo S200129m: Upper limits from CALET observations.
  75. LIGO/Virgo S200129m: NED Galaxies in the 50% Localization Volume
  76. LIGO/Virgo S200128d: upper limits from AGILE/GRID observations
  77. LIGO/Virgo S200129m: upper limits from AGILE/GRID observations
  78. LIGO/Virgo S200129m: Upper limits from IceCube neutrino searches
  79. LIGO/Virgo S200129m: Identification of a GW compact binary merger candidate
  80. Fermi-LAT ANTARES coincidence: IceCube neutrino search
  81. LIGO/Virgo S200128d: Upper limits from Fermi-GBM Observations
  82. LIGO/Virgo S200128d : no neutrino counterpart candidate in ANTARES search
  83. LIGO/Virgo S200128d: No counterpart candidates in HAWC observations
  84. LIGO/Virgo S200128d: Identification of a GW compact binary merger candidate
  85. LIGO/Virgo S200128d: Upper limits from IceCube neutrino searches
  86. GRB 200127A: Swift detection of a burst
  87. GRB 200125A: AbAO optical upper limit
  88. GRB 200125A: TNG detection of a NIR counterpart candidate
  89. IceCube-200120A: Event likely due to background
  90. GRB 200115A: Assy optical observations
  91. LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
  92. IPN Triangulation of GRB 200120A
  93. GRB 200122A: GOTO non-detection of optical afterglow
  94. GRB 200122A: Swift detection of a burst
  95. IceCube-200120A: Upper limits from a search for additional neutrino events in IceCube
  96. IceCube-200120A: not observable by Fermi-GBM
  97. IceCube-200120A: IceCube observation of a high-energy neutrino candidate event
  98. IceCube 200117A: No significant detection in HAWC
  99. LIGO/Virgo S200115j: No counterpart detection within possible host galaxies observed by the GRAWITA-Savelli telescope
  100. GRB 200115A: Mondy optical observations and correction to GCN 26790

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